Improvement in hydraulic or air car-brakes



V UNITED STATES PATENT QFFICE.

WILLIAM M. HENDERSON, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT IN HYDRAULIC OR AlR CAR-BRAKES.

Specification forming part of Letters Patent No. 143,980, dated October28, 1873; application filed September 22, 1873.

CASE B.

To all whom it may concern:

Be it known that I, WILLIAM M. HENDER- soiv, of Philadelphia,Pennsylvania, have invented certain Improvements in Hydraulic or AirGar-Brakes, of which the following is a specification My inventionrelates to that class of railroad-car brakes operated by fluid pressureand controlled by the engineer from the locomotive; and consists in theapplication of flexible diaphragms to fluid-containing vessels, withsuitable plungers or rams directly connected to the brake-beams.

The invention reduces the number of parts and effects a saving in firstcost, and of trouble and expense in subsequent maintenance. Thediaphragms are specially advantageous, as compared with pistons andcylinders in excluding dust, avoiding leakage, and dispensing with allpacking.

I will now proceed to describe particularly and exactly the manner inwhich my said invention is to be made and operated, referring, in sodoing, to the drawing annexed and the letters of reference markedthereon.

Figure 1 is a side elevation of a four-wheeled truck with this inventionapplied, and Fig. 2 is a plan of the same. Figs. 3 and 4 show anenlarged drawing of the brake-operating device, the former being a sidesection, and the latter an end view with one-half of the ram removed,showing the center chamber or drum.

The same letters of reference apply to the same parts in the severalfigures.

A represents a chamber, whose ends are formed of flexible diaphragms Band B, secured by flanges O and C bolted securely to the chamber A,making airtight joints. The edges of the openings in the chamber A andflanges O 0 should be carefully rounded, so as not to chafe or break thediaphragms. Against each of the diaphragms B and B are placed plungersor rams D D, whose outer ends are attached to the brake-beams E and E,bearing the brake-shoes F F. G G are guides passing through suitablelugs on the vessel A and outer ends of the rams D D, into thebrake-beams E E, supporting the vessel A and ramsD D in proper position.Fluid pressure is admitted or relieved through a tube connected at thebottom I of the vessel A.

When pressure is applied the diaphragms B B become inflated, and pressthe rams D D outward, and, by means of the brake-beams E E and shoes FF, the brakes are applied. When the fluid pressure is relieved thediaphragms collapse, and the brake-shoes F F no longer being pressed tothe wheels, they are free to rotate.

When an inelastic fluid is employed to 0p crate the brakes, I add anair-chamber, H, to the top of the vessel A, the function of which is tomoderate the action of the brake-shoes F F against the wheels toaccommodate any imperfections in circular form consequent either ondefective construction or unequal wear.

hen an elastic fluid is employed, then the air-chamber is unnecessary.

The vessel A may be used with a single diaphragm and ram, in which casethe vessel A must be connected with a pipe at I, of sufficientelasticity or flexibility to permit of motion in the vessel A inadirection opposite to the motion of its ram.

WVhen the brakes are applied to the outer sides of the wheels, insteadof the inner sides, as shown in the drawing, motion maybe trans mittedby rods reaching from the ram-heads to the brake-beams, without theintervention of levers. I

Having thus described my said invention, whatl claim as new and usefultherein is- 1. The combination of dish shaped diaphragms, with rams or.plungers directly'connected with the brake-beams and brake-shoes,substantially as and for the purpose described.

2. The combination of the air-chamber H with the vessel A, dish-shapeddiaphragms B, and rams D, having brake-beams E directly connectedtherewith, substantially as and for the purpose set forth.

WILLIAM M. HENDERSON.

Witnesses:

J NO. A. BELL, JOHN B. DEVINE.

